include/linux/sysfs.h

   1 /*
   2  * sysfs.h - definitions for the device driver filesystem
   3  *
   4  * Copyright (c) 2001,2002 Patrick Mochel
   5  * Copyright (c) 2004 Silicon Graphics, Inc.
   6  * Copyright (c) 2007 SUSE Linux Products GmbH
   7  * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
   8  *
   9  * Please see Documentation/filesystems/sysfs.txt for more information.
  10  */
  11
  12 #ifndef _SYSFS_H_
  13 #define _SYSFS_H_
  14
  15 #include <linux/compiler.h>
  16 #include <linux/errno.h>
  17 #include <linux/list.h>
  18 #include <linux/lockdep.h>
  19 #include <asm/atomic.h>
  20
  21 struct kobject;
  22 struct module;
  23 enum kobj_ns_type;
  24
  25 /* FIXME
  26  * The *owner field is no longer used.
  27  * x86 tree has been cleaned up. The owner
  28  * attribute is still left for other arches.
  29  */
  30 struct attribute {
  31         const char              *name;
  32         struct module           *owner;
  33         mode_t                  mode;
  34 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  35         struct lock_class_key   *key;
  36         struct lock_class_key   skey;
  37 #endif
  38 };
  39
  40 /**
  41  *      sysfs_attr_init - initialize a dynamically allocated sysfs attribute
  42  *      @attr: struct attribute to initialize
  43  *
  44  *      Initialize a dynamically allocated struct attribute so we can
  45  *      make lockdep happy.  This is a new requirement for attributes
  46  *      and initially this is only needed when lockdep is enabled.
  47  *      Lockdep gives a nice error when your attribute is added to
  48  *      sysfs if you don't have this.
  49  */
  50 #ifdef CONFIG_DEBUG_LOCK_ALLOC
  51 #define sysfs_attr_init(attr)                           \
  52 do {                                                    \
  53         static struct lock_class_key __key;             \
  54                                                         \
  55         (attr)->key = &__key;                           \
  56 } while(0)
  57 #else
  58 #define sysfs_attr_init(attr) do {} while(0)
  59 #endif
  60
  61 struct attribute_group {
  62         const char              *name;
  63         mode_t                  (*is_visible)(struct kobject *,
  64                                               struct attribute *, int);
  65         struct attribute        **attrs;
  66 };
  67
  68
  69
  70 /**
  71  * Use these macros to make defining attributes easier. See include/linux/device.h
  72  * for examples..
  73  */
  74
  75 #define __ATTR(_name,_mode,_show,_store) { \
  76         .attr = {.name = __stringify(_name), .mode = _mode },   \
  77         .show   = _show,                                        \
  78         .store  = _store,                                       \
  79 }
  80
  81 #define __ATTR_RO(_name) { \
  82         .attr   = { .name = __stringify(_name), .mode = 0444 }, \
  83         .show   = _name##_show,                                 \
  84 }
  85
  86 #define __ATTR_NULL { .attr = { .name = NULL } }
  87
  88 #define attr_name(_attr) (_attr).attr.name
  89
  90 struct file;
  91 struct vm_area_struct;
  92
  93 struct bin_attribute {
  94         struct attribute        attr;
  95         size_t                  size;
  96         void                    *private;
  97         ssize_t (*read)(struct file *, struct kobject *, struct bin_attribute *,
  98                         char *, loff_t, size_t);
  99         ssize_t (*write)(struct file *,struct kobject *, struct bin_attribute *,
 100                          char *, loff_t, size_t);
 101         int (*mmap)(struct file *, struct kobject *, struct bin_attribute *attr,
 102                     struct vm_area_struct *vma);
 103 };
 104
 105 /**
 106  *      sysfs_bin_attr_init - initialize a dynamically allocated bin_attribute
 107  *      @attr: struct bin_attribute to initialize
 108  *
 109  *      Initialize a dynamically allocated struct bin_attribute so we
 110  *      can make lockdep happy.  This is a new requirement for
 111  *      attributes and initially this is only needed when lockdep is
 112  *      enabled.  Lockdep gives a nice error when your attribute is
 113  *      added to sysfs if you don't have this.
 114  */
 115 #define sysfs_bin_attr_init(bin_attr) sysfs_attr_init(&(bin_attr)->attr)
 116
 117 struct sysfs_ops {
 118         ssize_t (*show)(struct kobject *, struct attribute *,char *);
 119         ssize_t (*store)(struct kobject *,struct attribute *,const char *, size_t);
 120 };
 121
 122 struct sysfs_dirent;
 123
 124 #ifdef CONFIG_SYSFS
 125
 126 int sysfs_schedule_callback(struct kobject *kobj, void (*func)(void *),
 127                             void *data, struct module *owner);
 128
 129 int __must_check sysfs_create_dir(struct kobject *kobj);
 130 void sysfs_remove_dir(struct kobject *kobj);
 131 int __must_check sysfs_rename_dir(struct kobject *kobj, const char *new_name);
 132 int __must_check sysfs_move_dir(struct kobject *kobj,
 133                                 struct kobject *new_parent_kobj);
 134
 135 int __must_check sysfs_create_file(struct kobject *kobj,
 136                                    const struct attribute *attr);
 137 int __must_check sysfs_create_files(struct kobject *kobj,
 138                                    const struct attribute **attr);
 139 int __must_check sysfs_chmod_file(struct kobject *kobj,
 140                                   const struct attribute *attr, mode_t mode);
 141 void sysfs_remove_file(struct kobject *kobj, const struct attribute *attr);
 142 void sysfs_remove_files(struct kobject *kobj, const struct attribute **attr);
 143
 144 int __must_check sysfs_create_bin_file(struct kobject *kobj,
 145                                        const struct bin_attribute *attr);
 146 void sysfs_remove_bin_file(struct kobject *kobj,
 147                            const struct bin_attribute *attr);
 148
 149 int __must_check sysfs_create_link(struct kobject *kobj, struct kobject *target,
 150                                    const char *name);
 151 int __must_check sysfs_create_link_nowarn(struct kobject *kobj,
 152                                           struct kobject *target,
 153                                           const char *name);
 154 void sysfs_remove_link(struct kobject *kobj, const char *name);
 155
 156 int sysfs_rename_link(struct kobject *kobj, struct kobject *target,
 157                         const char *old_name, const char *new_name);
 158
 159 void sysfs_delete_link(struct kobject *dir, struct kobject *targ,
 160                         const char *name);
 161
 162 int __must_check sysfs_create_group(struct kobject *kobj,
 163                                     const struct attribute_group *grp);
 164 int sysfs_update_group(struct kobject *kobj,
 165                        const struct attribute_group *grp);
 166 void sysfs_remove_group(struct kobject *kobj,
 167                         const struct attribute_group *grp);
 168 int sysfs_add_file_to_group(struct kobject *kobj,
 169                         const struct attribute *attr, const char *group);
 170 void sysfs_remove_file_from_group(struct kobject *kobj,
 171                         const struct attribute *attr, const char *group);
 172
 173 void sysfs_notify(struct kobject *kobj, const char *dir, const char *attr);
 174 void sysfs_notify_dirent(struct sysfs_dirent *sd);
 175 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 176                                       const void *ns,
 177                                       const unsigned char *name);
 178 struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd);
 179 void sysfs_put(struct sysfs_dirent *sd);
 180 void sysfs_printk_last_file(void);
 181
 182 /* Called to clear a ns tag when it is no longer valid */
 183 void sysfs_exit_ns(enum kobj_ns_type type, const void *tag);
 184
 185 int __must_check sysfs_init(void);
 186
 187 #else /* CONFIG_SYSFS */
 188
 189 static inline int sysfs_schedule_callback(struct kobject *kobj,
 190                 void (*func)(void *), void *data, struct module *owner)
 191 {
 192         return -ENOSYS;
 193 }
 194
 195 static inline int sysfs_create_dir(struct kobject *kobj)
 196 {
 197         return 0;
 198 }
 199
 200 static inline void sysfs_remove_dir(struct kobject *kobj)
 201 {
 202 }
 203
 204 static inline int sysfs_rename_dir(struct kobject *kobj, const char *new_name)
 205 {
 206         return 0;
 207 }
 208
 209 static inline int sysfs_move_dir(struct kobject *kobj,
 210                                  struct kobject *new_parent_kobj)
 211 {
 212         return 0;
 213 }
 214
 215 static inline int sysfs_create_file(struct kobject *kobj,
 216                                     const struct attribute *attr)
 217 {
 218         return 0;
 219 }
 220
 221 static inline int sysfs_create_files(struct kobject *kobj,
 222                                     const struct attribute **attr)
 223 {
 224         return 0;
 225 }
 226
 227 static inline int sysfs_chmod_file(struct kobject *kobj,
 228                                    const struct attribute *attr, mode_t mode)
 229 {
 230         return 0;
 231 }
 232
 233 static inline void sysfs_remove_file(struct kobject *kobj,
 234                                      const struct attribute *attr)
 235 {
 236 }
 237
 238 static inline void sysfs_remove_files(struct kobject *kobj,
 239                                      const struct attribute **attr)
 240 {
 241 }
 242
 243 static inline int sysfs_create_bin_file(struct kobject *kobj,
 244                                         const struct bin_attribute *attr)
 245 {
 246         return 0;
 247 }
 248
 249 static inline void sysfs_remove_bin_file(struct kobject *kobj,
 250                                          const struct bin_attribute *attr)
 251 {
 252 }
 253
 254 static inline int sysfs_create_link(struct kobject *kobj,
 255                                     struct kobject *target, const char *name)
 256 {
 257         return 0;
 258 }
 259
 260 static inline int sysfs_create_link_nowarn(struct kobject *kobj,
 261                                            struct kobject *target,
 262                                            const char *name)
 263 {
 264         return 0;
 265 }
 266
 267 static inline void sysfs_remove_link(struct kobject *kobj, const char *name)
 268 {
 269 }
 270
 271 static inline int sysfs_rename_link(struct kobject *k, struct kobject *t,
 272                                     const char *old_name, const char *new_name)
 273 {
 274         return 0;
 275 }
 276
 277 static inline void sysfs_delete_link(struct kobject *k, struct kobject *t,
 278                                      const char *name)
 279 {
 280 }
 281
 282 static inline int sysfs_create_group(struct kobject *kobj,
 283                                      const struct attribute_group *grp)
 284 {
 285         return 0;
 286 }
 287
 288 static inline int sysfs_update_group(struct kobject *kobj,
 289                                 const struct attribute_group *grp)
 290 {
 291         return 0;
 292 }
 293
 294 static inline void sysfs_remove_group(struct kobject *kobj,
 295                                       const struct attribute_group *grp)
 296 {
 297 }
 298
 299 static inline int sysfs_add_file_to_group(struct kobject *kobj,
 300                 const struct attribute *attr, const char *group)
 301 {
 302         return 0;
 303 }
 304
 305 static inline void sysfs_remove_file_from_group(struct kobject *kobj,
 306                 const struct attribute *attr, const char *group)
 307 {
 308 }
 309
 310 static inline void sysfs_notify(struct kobject *kobj, const char *dir,
 311                                 const char *attr)
 312 {
 313 }
 314 static inline void sysfs_notify_dirent(struct sysfs_dirent *sd)
 315 {
 316 }
 317 static inline
 318 struct sysfs_dirent *sysfs_get_dirent(struct sysfs_dirent *parent_sd,
 319                                       const void *ns,
 320                                       const unsigned char *name)
 321 {
 322         return NULL;
 323 }
 324 static inline struct sysfs_dirent *sysfs_get(struct sysfs_dirent *sd)
 325 {
 326         return NULL;
 327 }
 328 static inline void sysfs_put(struct sysfs_dirent *sd)
 329 {
 330 }
 331
 332 static inline void sysfs_exit_ns(int type, const void *tag)
 333 {
 334 }
 335
 336 static inline int __must_check sysfs_init(void)
 337 {
 338         return 0;
 339 }
 340
 341 static inline void sysfs_printk_last_file(void)
 342 {
 343 }
 344
 345 #endif /* CONFIG_SYSFS */
 346
 347 #endif /* _SYSFS_H_ */